Extensible chair



Feb. 5, 1929. 1,700,741 A A. J. MAY

nx'rmsmm cmun Filed May 1.7. 1926 7 Sheets-Sheet 1 INVENTOR as ATT N YS Feb. 5, 1929. 1,700,741

A. J. MAY

EXTENSIBLE CHAIR I Filed May 17. 1926 '1 sheets-sheet 2 IIIIIIIIIIIIII" INVENTOR fizam av. A I W) v zlsATT RNEYS Feb. 5, 1929.

A. J. MAY

EXTENSIBLE CHAIR 7 Sheets-Sheet 3 Filed May 17. 1926 A v 4 w 1 f g/l INVENTOR zf/F BY W W I LSATTORNEYS -t Feb. 5, 1929. f

1 1,700,741 A. J. M AY V EXTENSIBLE CHAIR Filed May 17. 1926 '7 sheets-sheet 5 iNVENTOR I %z1sAT o NEYs- Feb. 5, 1929.

- A. J. MAY

EXTENSIBLE CHAIR Filed May 17. 1926 7 Sheets-Sheet 6 IIFIII I I-lr ll-ll ll lllllllll llllillllll l INVENTO I f V LSATTO NEYS Feb. 5, 1929.

A. J. MAY

EXTENSIBLE CHAIR Fi-led ma 17.

19'ge 7 Sheets-Sheet 7 hfin M m 6 7 2 INVE 1% TT RNEY-S Patent ed Feb. 5, 1929.

ADAM amazon ROCHESTER, NEW YORK. assrenoia, BY Mam AssIeN'MnnTs, To BITTER DENTAL MANUFACTURING com any, me, or ROCHESTER, new YORK, A

CORPORATION-0F DELAWAR Application fi1ed.May 17',

The present invention relates to extensible chairs and has for its object to provide an improved raising and loweringmechanism applicable to dental, surgical, and other types of chairs andwhich iseilicient in operation and economical to manufacture.

A. further object or the invention is to provide an improved lifting mechanism for extensible chair sections embodying a flexible power driven connection, through the for elevating and lowering the sections whereby they are moved simultaneously one relative to another in either CllrCt10IL- A still further ob ect of the invent on is to provide an extensible chairjhaving telescoping sections guided within a-base or casing wherein one section is adapted to lift the other, the lifting section being elevated and lowered by means ofa flexible connection yieldably supported at one end whereby it is held taut and maintained in proper re lation with a power driven element operating in engagement therewith; I

To these and other ends the invention resides in certain improvements and combination of parts all as will be hereinafter more fully described, the novel features being pointed out in the claims at the end of the specification.

In the drawings: v I Fig. 1 is a side elevation of a chair enibodying the invention;

Fig. 2 is a top planview of the chair base showing the relative positions oit'h e telee scoping sections and the manner of guiding the. same; Y Fig. 3 1s a top plan oi the base 'shown partly in section to illustrate the motor drive mechanism for raising and lowering the telescoping sections; I

Fig. 1 is a vertical section taken on line 4ll* of Fig. 3, showing a portion of the driving mechanism for raising the chairsections; i i

Fig. 5 is a "fragmentary sectional elevation showing an adjustable connection for the lower end of one of the chains'interposed between the telescoping sections;

1 onlinef16?'-16 of Fi manner of attachingthe lower pulley to the f19 'and 20 at one si n TnnsIBLE CHAIR.

1926; Serial No. 109,560.

Fig. 6 is a part sectional elevation showing the telescoping sections inraised position;

V 7 is'a similar in lowered position; i g s 1 Fig. 8 is an enlarged detail vertical section showing a yieldable vanchor for one end of the flexible operating connection by which the sections are elevated.

Fig. Qis'acentral vertical section showing the chair sections inlOwered position" and illustrating a portion of the lifting mechanism'for the sections; g c I Fig. 10 is a vertical sectionztaken substantially on line 10"10 of Fig. 3; i

E1 11 is a top'plan of affiXed standard pro ectingwithin the telescoping sections as showninFiglO; "j I 12 a horizontal section of the stand,

Fig. 13 is a vertical section corresponding to Fig. 10 and showinga modifiedform oi the invention; i i

Fig. 14 is a diagrammatic view view with; the sections in elevation and partly in section showing the moditive positions of the pulleys an'd'connections 1 for the sprocket chain by which the outer column is'raised; and v I v p Fig. 16 1s a fragmentary vertical section gure 13'; showing the outer column. I

Similarv reference numerals throughout the several views indicate thesame parts. The embodiment of theinventiondisclosed herein by way of illustrationof the principles involved comprises preferably a base. indicated generally at lO and a chair seatframe llupon which'is' supported a seat orcushion 12, afoot rest 13, a back 14, side arms15 and other parts asshown in Fig. 1,,all of which may be of any approved or well known construction. The base, which may be of any desired shape, preferably comprises upper cylindrical sectionor' casting 16'and a lower flanged section 17 connected preferably as indicated in Figs. 9 and 1O the stud.

bolts 18.

The. upper and lower casing sections are '22'and 23 respectively which are adapted to'rest upon the bottom 24 of the base section 17 when the columns are in their lowermost position as shown in Fig. 10. ,The seat frame llflfor supporting the frame 11 is carried by the inner section 22 being connected therewith by a flanged ring 26 secured preferably by. a suitable number of screws26, one of which is shown in 9, the screws being threaded into openings 26 which areindicated in Fig. 2. The seat frame is held upon the ring by a plate 27 forminga closure for the upper end of the section 22 and'being secured to the ring by a suitable number of screws 28. V

The shape of the extensible sections 22 and 23 is best indicated in Fig. 2, theouter section having oppositely disposed side portions 29 each ofwhich is provided with a pair of vertically extending angularly disposed i tracks 30 upon Which travel the guide rollers 31 which are suitably journaled in bearings 32 projecting inwardly from the base 10.

Any number of the rollersmay be provided,

preferably one pair for each track, only one of which is shown. Theinner section 22 is guided by the outer section, the former having laterally projecting and vertically ar- 7 ranged extensions 33 each having a track 34 upon which a suitable number of rollers 35 are adapted to travel, said rollers being j ournaled in bearings 36 on the inner face of the outer section 23 as shown in Fig. 2.

Projecting upwardly within the section 22 is av standard 37 provided with an enlarged.

base portion 38 having two sets of'projecting lugs 39 and 40 each of which is adapted to rest upon the bottom 24 of the base and to be secured thereto by screws or bolts, not

shown, arranged to extend through openings 41 inthe lugs. The base portion 38 of the standard 37 is provided with a vertically dis- 43 on a drive shaft 44 having its inner end 'journaled in a bearing 45 secured in a pocket or recess 46 of the standard 37 as shownin Fig. 10. The outer end of the shaft 44 is journaled in a bearing 47, seated in a frame or gear casing 48 as best shown in Figs. 3 and 10, theframe being carried by the bottom 24 of the base to which it is secured by screws 49. The shaft 44 has a gear 50 suitably secured thereon which is in mesh with a gear 51 free to rotate upon an arbor 52 supported bythe frame 48 as shown in Fig. 10; The gear51 is driven by a pinion 53 on a short shaft 54 suitably journaled in the frame 48 and carrying a worm wheel 55. A worm 56 upon a shaft 57 serves to drive the worm wheel. The worm shaft is suitably j ournaled in a pair of bearings supported by the frame 48 and is connected with .the armature shaft 58 of the motor 21 by a suitable coupling 59,

preferably one'of the flexible type.

The standard 37 is of the hollow type as lower end of the outer column .23, said pulley being carried by a pin 66 having its opposite ends supported by said lugs. The pulley 64 projects through a slot 67 in the outer column and also into a slot 68 in the bottom 3 of the inner column when the latter is in lowered position as shown in Fig. 9. I

The lifting element for the outer column comprises a flexible connection 69, preferably in the form of a chain and having at its outer end an adjustable bolt comprising a cylin- 71 projecting through'and having its head resting upon a bar 72 supported by lugs 7 3 drical' nut 70 into which is threaded a screw extending inwardly from the casing 16 as shown in Figs. 2 and 9. The connection .69

extends downwardly around the pulley: 64,

thence upwardly within the inner column 22 and over the pulley 62 and then down through the standard 37 around the sprocket 43and upwardly a short distance where it connects with a rod 74. The. rod extends vertically within the column. 12 and projects into a pocket 75 formed in the upper end of said column as shown in Fig. 9. A spring 76 surrounds therod within the pocket, the tension of the spring being regulated by 'a screw 77 threaded into the rod as shown in Fig. 8. The spring serves to hold the chain taut under all conditions of operation and maintains the rollers of the chain in proper engagement with the teeth of the sprocket, both during the ascending and descending movev .ments of the sections. posed recess 42 for the reception of a sprocket The use of the spring or a yieldableanchor for the chain is an important feature ofthe lifting mechanismand is essential to the suca binding action might take place between the teeth and the rollers which might result in bending or breaking the teeth of the sprocket or in the in ture of the chain. This dificulty is avoided .liy employing the yield-.

able means shown for keeping the chain taut during the descent of the inner and outer It'will be understoodfrom theconstruction described above thatthe' motor serves to drive the sprocket 43 and thatirotation of the latter in the direction indicated by the arrow in Fig.

. 9 will exert a pull onthe chain which will elevate the outer column or section 23.

Raising of the inner column is effected at the same time by movement of the outer col umn, through the use of a pair of flexible c011 nections. or chains 7 8, each .extending over a 1 pulley 79 rotatably mounted upon the inner face of the outer column 23 asshown in Fig.

; 10. One end of each chain 7 8 is connected to a-lug 80 projecting from the innercolumn vnear the bottom thereof, the opposite end of the chain being-connected with an adjustl able' anchor-81 having a depending portion 82 guided in a recess '83 formed in the bottom 24 of the base as shown in Fig. 5. The anchor Zmay be adjusted vertically from time-to time by a screw 84 to-takeup slaclrin the chain,

the screw being extended through a laterally pro ecting portion 85 of the anchor and threaded intothe bottom 24 of the base as shown. I I

It will be apparent fromjthe construction just described that raising of the outer sec tion through the medium ofv the sprocket 43 and chain 69 will jefliect simultaneous raising I of the inner section 22, since the chain 7 8, ext

tending over the pulley 79 of the outer sec tion, has oneend fixed to the bottom ofthe base and the other to the bottom of the in- ,ncr section 22. Furthermore it will be apaarent that the inner section will move twice asvfast as the outer sectionl since the movement' of the chain is twice that of themove- Inentofthe outer section. i

In the downwardmovement of the sections the motor is ofcourse reversed, so thatthe pull of the sprocket-is transferred to the in ner section 22 through; the rod 74 and spring 76, the outer section beinglowered 'atthe same time by. the return movement of the I chain 69 trzwelingoverv the pulley 62 as. will be understood. 5

The standard 37,-the inner section 22 and outer section 23 areeach slot-ted as indicated at 86, 87, and 88 respectively to afford clearance for the sprocket shaft 44; as shown Fig. 10. I J

The casing 16 is provided at itsupper end with a cover 89 having opening through which the chair. raising sectionsoperate and i "the outer section is provided with acove'r through which the innerisection 22iprojects as shown in Fig. 9.

' f The eiectric switch'forcontrolling the operation of the motor, notshowrnxis preferably controlledby afoot pedal 92 located at one aside oft-he chair base as-shown in 3f" In the modificationshownin Figures 13 to -16 inclusive, the base-.10 is similar to the base I shown in Figures 1 to 3and' 9 andflO with but I y slight differences, as will appear hereinafter. The base 1Q comprises the-upper and lower sections 16 and 17, respectively, the latter having a b otton124 upon which normally rests the inner and outer extensible chair raising sections 22 and 23, as shown in Figure 13. The casing sections 16 and 17" are provided with extended portions 19 and 20 toiwhich the reversible motor for raising the .chair sections is secured, as shown in Figure 3. The gear arrangement-driven by the motor 21 for raising the sections is shown in Figure l lis the same as that shown in Figure 10, being giventhe same reference characters.

Thes'procket shaft 4% which is driven by the and 45 the latter extending upwardly from the bottom 24 of the base, as shown in Figure 14. A sprocket 13 is fixed on the inner end I of theshaft and is operatively associated with the chain or flexible connection 69? as shownin Figure'13. The chain is secured atone endQto an adjustable connection com-' prising a cylindrical nut 70* and a screw 71? gear 50 is suitably journaled in bearings 17 threaded into the nut. The connection extends through and is supported by a lug 73? shown in Figure 15. The chain extends down wardly from said lug around a pulley 6 1 on ;:projecting inwardly from the casing 16 as I the bottom of the outer ch airraising'section H i23f andis carried upwardly over a pulley 62 having a spindle 63 journaledin a bearing 63 projecting inwardlyfrom the casing 16 as shown in Figure 15. I The chain is carried downwardly from the pulley 62 around'the' sprocket 43 and thence upwardly ashort distance whereit connects with a rod 7.4

pThe upper end ofthe rod projects into a recess or pocket 75 formed in' the outer end of an arm or bracket 22 extendinglaterally from .the topfiof the inner chair ra1singsec- 'tion.22 The outersection23 is cutaway at 23 to'afford clearance for the arm, as shown '115 in Figures 13 and15." The arm may be cast j integral with the inner chair raising section 1 or otherwise-secured thereto asdesiredf 1 The rod 7 1% is connected at its u-pper' end with a spring 76* which surrounds the. rod

within the recess 75 of the'arm, the tension of the spring being regulated-by a screw 7.

threaded into the rod and engaging the upper end of the spring. The spring-servesto hold thechain tautunder all conditions 'ofopera tion, being providedzfor the same purpose and functioning in the samemanner as the spring 76 shown in Figure 9. I I

I The pulley 64* on the lowerendof the outer chair raising section 23 is preferably carried .thecha-ins 7 8 shown in Figure 10,'said chains 7 I being extended over pulleys 79 journaled on the'inner face of the outer column 23 as shown in Flgure 14L The outer and inner sections are guided by the rollers 31 and 35 in the same manner as shown in Figure 2.

The operation of the modified arrangement'is the same as that embodied in-Figures 1 to 12 inclusive, the same motor and driv- "ing mechanism being employed in both cases, i

outer chair raising sections. gulded .w1th1n the principal difference being in omitting the central standard 3'? as a support for the intermediate chain carrying pulley 62, this pulley in themodified arrangement being secured to the top of the casing'lG so that'the chain 69 may operate entirely between the outer chair raising section and the casing surrounding the same. a g j r I claim as my invention: 7

1'. In an extensible chair, a base, a column disposed therein, a second column within the base, means operatively connecting the first mentioned column with the second to'eflect raising of the latter, a flexible connection interposed between the second mentioned column and the base and operatively connected with the first mentioned column to! effect raising of the same and means operatively engaging said connection.

2. In an extensible chair,-a base, inner and outer extensible columns adapted to be guided within the base,'a flexible connection interposed between said base and one of said columns and operatively connected with the other column to effect raising of the first men 'tioned column, means connecting the last mentioned column with the base toraise said last mentioned column and means operatlvely engaging said connection.

'3 ii an extensible chair, a base, inner and outer extensible columns adapted to be guided inthe base, a flexible connection having one end anchored upon the base and the other upon one of-said columns,-a rotatable member upon the other of-said columns on which said connection is adapted to travel,'means actuated by the last mentioned column for lifting the other column and a driven member operatively engaging said flexible connection. I

4. In an extensible chair, a base, inner and outer chair raising sections guidedwwithin the base, a flexible connection operatively associated with the outer section andhaving one end, anchored upon the base'and the other connected. with the innersectioma re volvable support v upon which the connection is adapted-to travel, actuating means for said connection and'means "for-moving. the

inner section relative to theioutersection.

. 5. In an extensible chair,.a base, inner and outer. chair raising sections guided'withln the base, a pulley ijournaled upon the outer} section, a second pulley supported within the base,.a flexible conn ection engagingsaid' pul same, means for driving said revolvable member'and means adapted to'be operated. by the outer section to effect raising of the inner section. 6. In an extenslble chalr, a base, lnner and the base, a chain operatively associat'edwith the outer section and having one end anchored upon the base and the other upon the inner section, actuatmg means for said chain including a sprocket and means actuated by section. v

7.'In an extensible chair, a base,1nner and outer chair ra sing sections gulded withthe outer section adapted to raise the; inner in the base, a flexible operating'ronnection, having one end anchoredupon the base and the other upon the inner section andbeing connected intermediate its ends with the outer section, a pulley connected with the ,base and forming a support uponwhich said operating connection is adapted to travel, actuating means "for said-connection and flexible devices actuated by the outer section adapted to move the inner section relativeing one end anchored upon thebase and the other upon the inner section, a revolvable support carried by the baseupon whichthe flexible operating member is adapted to travel, means connecting said flexible connection with the outer: section to effect raismg of thelatter, means for actuating said connection and means located between the inner and outer sectionsadaptedlto be actuated by the latter to raise the'former.

"19. In an'extensiblechair, a base, in'nerland Y outer chair raising sections supported by the base, a pulley 'journaled upon the outer section, a support projectingwithin the inner section, a pulley mounted on said support, a flexible operating member engaging said pulleys and having one end anchored upon the base and the other upon the inner section, means for actuating said flexible mem ber to elevate said outer section and means actuated by the outer section ad t g m raise theinner section. I 7

10. In an extensible chair, a base,-a column disposed therein. a second column within the base, means operatively connecting the first column with the second to effect lifting of the latter, a chain operatively associated V with the first mentioned column and having one end yieldably connected with the second mentioned column and the other connected with the base and actuating means for the chain including a sprocket. I Y

11. In an extensible chair-,a base, a column disposed therein, a second column within the base, means operatively connecting the first column With the second to effect lifting of the latter, a flexible connection operatively V associatedwith the first column andhaving one end anchored upon the base and the other raising of said first column.

In an extensible chair, a base, a chair raising column disposed therein, a support I so yieldably connected with the second column, a power shaft, and amember driven thereby adapted to actuatesaid connection to effect within the base,.afiexible connection operatively associated with said column and 'hav-, ing one end secured upon the support and the other upon the base, actuating means for said connect1on, and means operatively connectmg the support with said column.

13. In a lifting mechanism, a base, extenj 1 sible sections therein including an operated and actuating section, means operatively connecting the actuating section withthe other section, a flexible element interposed between the operated'section and the base, said element being operatively connected with the actuating section, and operating means for said flexible element. I V V 14. In a lifting mechanism, a base, extensible sections therein, a flexible connection in ,terposed between the sections adapted to operatively connect-one with the other, a flexible elementinterposed between the last mentioned section and the base and operatively associated with the other section and actuating means for said flexible element.

15. In a lifting mechanism, a base, cXten sible sections therein, means operatively con? necting one of the sections with the other, a flexible element interposed between the last mentioned" section and the base and having a yieldable anchor at one end, means operatively connectingsaid element with said last mentioned section, andoperating means for.

said element.

16. In a lifting mechanism, a base, inner and outer extensible sections therein, means operatively connecting the outer section with V the inner section, a flexible element interposed between the inner section and the base tion, and means for actuating said element.

17. In a lifting mechanism, a base, lnner andoperatively connected with the outer secand outer extensible sections therein, a flexc ible connection interposed between the inner and outer sections whereby the latter is adapted to lift the former, a flexible element operatively connected with the outer section having one end yieldably connected with the inner section andthe other connected With the base, and actuating means for'said element.

' 18. In anextensiblechair,abase,acolumn therein, a second column within the-base, means operatively connecting the first mentioned column withthe second column to effect raising ofthe latter, a pulley secured upon the base, a second pulley'secured upon the first mentionedcolumn beneath-the first mentioned pulley, a flexible operating c )n nection for said first 'mentione'd column adapted to extendaro'und said pulleysand having one end connected with the base and the other with the second mentioned column, and actuating means for said connection.

19. In an extensible chair, a base, inner and outer columns therein, means operatively, I 7

connecting the outer column with the inner columnto effect rais'ingof the latter, pulleys arm projecting" laterally from the inner 7 column to a point between the outer column and the base, a flexible element operatively connected 'withthe first mentioned column and having one end connected with said arm and the other with the base, actuating means for said flexible element, and means operatively e t gthe outer'column with th inner column.

21. In an extensible chair, a base, inner and outer chair raising. columns thereiman arm projecting laterally from the innercolumn to a point between the outer column and the base, a pulley secured uponthe upper end of the base, a second pulley secured upon the g I outer column adjacent the bottom thereof, a chain extending around said pulleys and having'on'e end anchored upon the baseand the other upon said arm, a power shaft having a sprocket thereon operatively engaging said chain, and means operative-1y connecting the. r

outer column with the inner, column,

AnAMa Ar; 

